The past few days, the game's been running fine. I try to run it today, and it won't boot up. I get the "now loading" mouse cursor for about a fourth of a second, then nothing. If I try running the game from the site, it instantly shuts down my browser without so much as a trace of the game itself.
Java's fully updated, graphics drives are updated, tried restarting my computer twice, and there's no firewall issue. I easily meet the minimum requirements as I played fine the past several days and fought Vanaduke fine as well.
I'm pretty sure that I don't have the game installed locally, I'm not sure how I'd do that. I couldn't uninstall it because it has no home folder and it's not in add/remove programs.
That's about all the info I can provide.
Try and see if the installer will work so you start the game from the Desktop instead. Head over here to get the client: http://download.threerings.net/spiral/client/spiral-install.exe